The present invention relates generally to an apparatus for storing tape which is fed to a printing apparatus, and more particularly to a tape storage apparatus for use in a mailing machine in which tape is selectively moved to and from a printing position in which postage indicia is printed on the tape when the mailing machine is not printing the postage indicia on discrete envelopes.
Modern day mailing machines, such as that shown and described in the aforementioned U.S. Pat. Nos. 4,876,956 and 4,922,085 have evolved into highly, multi-functional machines capable of processing a plurality of mail pieces of different types through the steps required to affix proper postage to them for handling by the U.S. Postal Service. For example, the mailing machine just mentioned can store a plurality of mail pieces in a hopper, successively feed them seriatim to a weighing module which electronically determines the amount or postage required for each mail piece, print that amount of postage as an indicia either directly on the mail piece if it is relatively thin, such as a typical letter envelope or on a strip of tape which is applied to the envelope if it is too thick to feed through the printing mechanism, and finally deposit mail pieces in an orderly fashion in any of a variety of stacking devices for retrieval and further handling by Postal Service representatives. It should also be noted that the foregoing process occurs at a high rate of speed, usually in the order of 2 per second if weighing each piece is involved, 4 per second if weighing is not involved. Thus, it will be apparent that to accomplish this process at the indicated speed, the mailing machine requires a great number of mechanical parts which must fit together accurately and operate smoothly, and a highly complex electronic control system including various operator controlled devices and modules for setting up and operating the mailing machine, microprocessors for controlling the synchronous operation of various components and devices, and diagnostic systems for detecting various malfunctions and providing appropriate indication thereof.
One of the requirements of the mailing machine under consideration is that of providing a continuous supply of tape on which the postage indicia is printed when tape printing is the selected mode of operation. Since the mailing machine operates at a high rate of speed in terms of the number of mail pieces processed as mentioned above, it is necessary to have a large supply of tape available in order to minimize the down time of the mailing machine which would otherwise be required if rolls of tape had to be replaced frequently. In addition, in order for the tape feed mechanism of the mailing machine to function smoothly and properly at a high rate of speed, it is necessary to have a tape storage mechanism which incorporates devices, controls and features for physically storing a large quantity of tape, for maintaining proper tension on the tape during intermittent feeding operations, for detecting when the tape becomes exhausted, for providing proper indication when this occurs, and being mounted in such a manner that it is structurally integrated into the mailing machine for maximum functionality and yet is conveniently accessible to machine operators or service personnel for their respective needs.
In the course of the design and development of the mailing machine with which the present invention was intended for use, many different design concepts were considered for an apparatus which would provide all of the functional requirements mentioned above. All of those considered provided some of these requirements with varying degrees of success, but each failed in one or more respects to meet the design criteria specified. For example, one design called for the tape storage apparatus to swing upwardly on an arc about a pivot point, but this resulted in so much slack in the strip of tape between the roll in the storage device and the input point of the mailing machine that it was difficult to thread the lead edge of the tape into the mailing machine. Another solution was to use two rolls of tape mounted side by side in the tape storage apparatus, but this was considered wasteful, inefficient and added unnecessary complexity and cost to the apparatus.
One particular vexing problem was that of structurally integrating the tape storage apparatus into the mailing machine in a manner which achieved maximum functionality while at the same time maintaining the apparatus conveniently accessible to operators and service people. It was found that when the tape storage apparatus was located when it would function best with the mailing machine, it was virtually completely inaccessible for replacement of rolls of tape or other service; and if located to facilitate access, certain functional problems developed in connection with the smooth feeding of tape from the storage apparatus to the printing module of the mailing machine which were unacceptable, such as difficulty in threading tape into the mailing machine and jamming and tearing of the tape during operation. Thus, prior to the present invention, there was no completely satisfactory tape storage apparatus available for use with the subject mailing machine.